1. Field of the Invention
The present invention relates to an apparatus for illumination comprising at least one housing suited for in ground use, which housing might contain at least one lamp, which lamp can be surrounded by reflective means, which housing further can comprise light changing means, which housing also can comprise control means for controlling at least the lamp and the light changing means.
The present invention also relates to a method for preventing moisture build-up inside an apparatus for illumination, which apparatus contains at least one lamp, which lamp is surrounded by reflective means which apparatus is communicating with control means for controlling at least the lamp.
2. Description of Related Art
U.S. Pat. No. 6,210,014 describes a material and a system for reducing condensation in enclosed vehicle lamp housings, and more particularly a condensation vent comprising a water vapor material within, on or integrated with the housing to reduce the condensation and prevent or minimize entry of liquid water and/or other foreign matter.
U.S. Pat. No. 6,210,014 describes a lamp used in a car where an opening in the upper par of the lamp is covered by a diaphragm for venting the lamp. Inside the car, the car itself protects the venting opening so that no mechanical damage occurs to the diaphragm. Using an upwards pointing diaphragm for in ground use will be completely impossible because in ground devices are subjected to the outdoor environment. In ground installations could often be placed where people are walking or even where cars are driving. This means, that a diaphragm would be subjected to pressure, which would destroy the diaphragm immediately. At least, a kind of mechanical protection is necessary. The diaphragm must be protected from being overflowed because the diaphragm is tight for water from the outside, in the overflowed situation, it will also be tight for water from the inside. In this way, the technology described in U.S. Pat. No. 6,210,014 could not be used for an in ground installation.
U.S. Pat. No. 6,540,374 describes an in ground lighting fixture having multiple separate and watertight compartments for the various components of the fixture, allowing for maintenance and service of the fixture without exposing weather-sensitive components to the elements. The fixture also includes a pan and tilt assembly, which can be selectively controlled with a common household tool to change the direction of the light without having to access the pan and tilt assembly.
U.S. Pat. No. 6,540,374 describes a water tight compartment for in ground use, but the document does not describe any effective ventilation means, which may lead to the fact that water inside the in ground lighting fixture will condensate on the inner side of the outside surfaces including the top window which is visible from the outside. During operation, the temperature inside the lighting fixture will increase, and the water inside will evaporate. An increasing pressure will probably press part of the moisture out through openings, but as soon as the lamp is shut off, the temperature drops which leads to a pressure reduction inside the in ground lighting fixture, and probably at least over time, air with a high moisture content is sucked back to the inside of the in ground lighting fixture. The reduced pressure inside the lamp housing could lead to a flow of water through the connecting cables. The cables might be placed deeper in the ground than the lamp and the cables might be surrounded by water. A reduced pressure in one end of a cable starts a pumping effect, which can lead to an inflow of water into the lamb housing.